Learn Hydroponics

Hydroponics is a century old system for growing plants without the use of soil, by immersing their roots in a nutrient-rich solution instead. Aside from not requiring soil, hydroponics also enables the recirculation of water through the system, drastically cutting the volume of water necessary for growth.

Getting Started

Hydroponic systems fall into two major types: those in which the plant roots are suspended in only the mineral solution (solution culture) and those in which the plant roots are immersed in another solid medium, like gravel or clay pebbles (medium culture).

The techniques for executing hydroponics range from the very simple to the considerably complex. The simplest technique, hand watering, involves suspending the plant roots in water or a substrate and adding water to the system often enough to keep the roots submerged at all times.

Techniques

Plants need to have fresh nutrients available for healthy growth. Ensuring regular reservoir changes every week is essential. pH and electro conductivity should be checked while mixing the nutrient solution. While the electro conductivity reading will help determine the amount of dissolved nutrients, the pH reading will help in maintaining pH values at levels that will enable plants to absorb the nutrients.

Static solution culture involves growing the plants in water containers, which can vary in size from mason jars to giant industrial tanks. Air is usually introduced into the system to encourage the flow of nutrients from the solution to the plant roots. Nutrients are added to the solution based when needed.

Continuous-flow solution culture uses a mechanical component (a pump) to continuously move nutrient rich-solution past the plant roots. By keeping the solution in circulation at all times, it attempts to deliver the maximum amount of nutrients and oxygen to optimize plant growth.

Substrates

“Substrates” refer to the solid (non-soil) materials in which the roots of the plants are suspended in medium culture aquaponics.

The most popular mediums are:
~ Baked clay pellets – these are reusable and environmentally friendly.
~ Growstones – made from recycled glass, a good alternative to clay pellets.
~ Rock wool – made from rock that is spun into tiny mineral fibers that then have capillary action (bringing solution across fibers to the roots)
~ Coco Peat – made from coconut shells, this medium is great at storing nutrients.
~ Gravel – gravel is inexpensive and will last forever, but adds considerable weight to the system.
~ Keeping a gardening journal will help in avoiding mistakes and establish pointers to the right course of action. Making journal entries regularly will, in the course of time, help build up a veritable treasure trove of valuable information on various aspects of nutrients, pH, EC etc.   

Nutrients

There are many different nutrient solution recipes, but nearly all of them include some combination of the calcium, potassium, magnesium, nitrate, and sulfate as the main nutritional ingredient.

If you’re just starting out, you might want to go with one of the many mixes available, which are optimized for particular systems and particular plant types. As you experiment further, you will have the opportunity to see what solution gives you the best results and maybe even work on your own custom nutrient mix.

Basic Equipment

One of the major draws of the hydroponic system is how easy it is to get started. You could put together a hydroponic setup in a jar or pot, buy some nutrient mix, and start growing plants immediately.

If you have more room, raised garden beds will allow you to grow a larger quantity of plants, either indoors or outdoors.

Recently, vertical walls have become popular as hydroponic systems. These feature a thin plastic or wooden wall embedded with a substrate, which can grow grass or leafy vegetables (the plants must be light) on one of the walls of your apartment. A spray bottle is usually used to keep the wall moist at all times, though more complex vertical watering systems also exist.